There are multiple differentials for a generalised increase in bone density which includes:

1. Myeloproliferative disorders such as myelosclerosis - here the bone marrow cavity is narrowed by endosteal new bone. You get patchy lucencies due to persistence of fibrous tissue alongside generalised osteopaenia in the early stages due to myelofibrosis. Classically, you also get hepatosplenomegaly.
2. Metabolic conditions such as renal osteodystophy
3. Poisoning secondary to fluorosis which results in a periosteal reaction most marked in the innominate bones and lumbar spine. For those of you unsure what the innominate bones are, this is the fused bones of the pelvis either side of the sacrum which compromises of the ischium, pubis and ilium. Due to the periosteal reaction you get prominent muscle attachments and calcification of ligaments and interosseous membranes.
4. Neoplastic which includes:

• osteoblastic mets most commonly from prostate and breast cancer
• lymphoma
• mastocytosis - here you get diffuse sclerosis of marrow containing skeleton with patchy areas of radiolucency which is classically the axial skeleton and ends of long bones. You also classically you get associated urticaria pigmentosa and also signs and symptoms of carcinoid syndrome such as:
  • flushing
  • hypotension and syncope
  • abdominal pain
  • nausea, vomiting and diarrhoea
  • malabsorption